684556169 has 6 divisors (see below), whose sum is σ = 752446170. Its totient is φ = 622323680.

The previous prime is 684556151. The next prime is 684556177. The reversal of 684556169 is 961655486.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 644550544 + 40005625 = 25388^2 + 6325^2 .

It is not a de Polignac number, because 684556169 - 2⁸ = 684555913 is a prime.

It is a super-2 number, since 2×684556169² = 937234297031913122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (684556069) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2828624 + ... + 2828865.

It is an arithmetic number, because the mean of its divisors is an integer number (125407695).

Almost surely, 2^684556169 is an apocalyptic number.

It is an amenable number.

684556169 is a deficient number, since it is larger than the sum of its proper divisors (67890001).

684556169 is a wasteful number, since it uses less digits than its factorization.

684556169 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5657511 (or 5657500 counting only the distinct ones).

The product of its digits is 1555200, while the sum is 50.

The square root of 684556169 is about 26164.0243273087. The cubic root of 684556169 is about 881.3255543826.

The spelling of 684556169 in words is "six hundred eighty-four million, five hundred fifty-six thousand, one hundred sixty-nine".